Lightweight and rather compact, the CAMP USA Tethys Pro Small Mobile Pulley easily carries on your harness and attaches to ropes up to 13mm. Like its less-intensive sibling, the Small Mobile Pulley, the Pro features an aluminum alloy body and stainless steel axle for durability on climbs and rescue scenarios. Unlike the Small Mobile Pulley, the Pro uses sealed ball bearings for high efficiency (92%) and intensive use at higher speeds. This pulley is prusik-minding, so it makes for ease in rigging a hauling system on routes or managing emergency rescue situations. Plus, it features a large connection point that accommodates two carabiners, as well as rotating side plates.